1. Field of the Invention
The present invention relates generally to a system for dissipating waste heat from heat generating equipment such as electronic components borne by satellites when in orbit. While the invention will be described in the context of a geosynchronous satellite, it will be understood that the teachings of the invention are applicable to any kind of a satellite whether in earth orbit or in some other orbit.
2. Description of the Prior Art
Communication satellite payload power requirements continue to rise. The increase in satellite payload in turn requires that the satellite allow for (a) increased equipment mounting area, and (b) increased waste heat thermal dissipation. In addition it is highly desirable that this increased capability be accommodated with the minimum increase in the satellite mass and size. The former requirement is obvious as launch cost tends to be proportional to mass. The latter requirement is based on the same issue in that larger satellite require in turn larger fairings which are heavier, have greater aerodynamic drag (reduced lift capability), and are more costly.
The two conventional approaches for addressing the above issues are
1. increase of the satellite body size thereby increasing its equipment mounting area and thermal radiating area which in turn increases the dissipation capability; the problem with this approach is that the larger satellite requires a larger fairing hence reducing launch mass per the above discussion; and PA1 2. use of deployable thermal radiators to increase the total satellite radiating area; this approach does not address the mounting area requirements and adds mass for the deployable radiator. PA1 1. Use of a double ended battery sleeve surrounding each cell (see detail provided in FIGS. 5 and 6) which acts to conduct heat to both radiator faces. This approach has the added benefit of eliminating the need for battery stiffening hardware as the two radiator panels act intrinsically as stiffening members. PA1 2. Selectively mounting bus equipment to the two faces which both distributes bus equipment heat and increases total mounting area (see FIGS. 5 and 6).
The ideal solution would be one in which equipment mounting and thermal dissipation areas are increased in a satellite of small body size. The problem is identification of available surface area. In present satellites about 80% of the North-South panel area is already occupied with payload equipment. The East-West faces are typically divided between the battery radiator and the output multiplexer (OMUX) for a communication satellite, a non-electronic component capable of operating at high temperatures and capable of usefully dissipating heat even when its mounting surface is subject to direct solar illumination. The earth deck is increasingly filled with communication receiving equipment. Only the anti-earth deck remains largely unoccupied, however, as this surface is subject to 12 hours of direct solar illumination every day and therefore is not generally useful by itself as a thermal radiator.
It was with knowledge of the foregoing state of the technology that the present invention has been conceived and is now reduced to practice.